Improvements to an auxiliary element for the segmental distalization to the canine-to-molar posterior maxillary area in orthodontic treatments

ABSTRACT

The improvements are characterised in that the ball joint of the median segment is spherical with two diametrically opposed planar faces in the positions of polar segments of the sphere and the arm of the median segment is joined to the ball joint forming a small acute angle.

The present invention is intended to disclose improvements to thesubject of the main patent No. 200102210 for an “Auxiliary element forthe segmental distalisation of the canine-to-molar posterior maxillaryarea in orthodontic treatments”.

The present improvements are the fruit of the experience acquired in theimplementation of the main patent and its first application of additionand enable the means required to achieve a better articulation betweenthe median segment and the distal segment to be considerably simplifiedwhile allowing the two elements to be connected merely by pressure andallowing free rotation within a large sector of the ball joint withinits recess in the distal segment and similarly allowing sufficient playin the lateral rotation and on the axis of the median arm for adjustmentof the median segment to the distal segment.

The objectives of the invention are achieved by the formation of theball joint with a spherical form with two opposed flat polar caps ofsignificant dimensions and with the arm of the median segment inclinedat an acute angle to the plane of symmetry of the ball joint. The recessin the distal segment has a form which partially mates with that of theball joint, with semi-closed edges at the mouth to allow retention ofthe ball joint merely by pressure within the recess and with a dimensionbetween faces which is somewhat greater than that of the ball joint toallow the lateral play of the median segment at the desired angle.

To assist comprehension, drawings of an embodiment of a distalisationarrangement according to the present invention are attached asnon-limiting examples.

FIG. 1 is a section of a detail of the articulation of the mediansegment and the distal segment.

FIG. 2 is a section through the indicated sectional plane.

FIG. 3 is a perspective view of the articulation shown in FIGS. 1 and 2.

Referring to the figures, the present invention resides in forming theball joint 1 with a curved surface shape, preferably as a sphere withdiametrically opposed planar polar segments 2 and 3 forming respectiveplanar faces which are perpendicular to a diameter 4 of the sphericalsurface. The remainder of the surface of the segment is curved,preferably spherical. The median arm 5 may be joined to the ball joint1, forming a small angle to the plane of symmetry thereof, this anglebeing indicated by the letter α in FIG. 2.

The recess produced in the distal segment 12 has a shape whichsubstantially mates with a portion of the ball joint, with a lateralsurplus which allows lateral play and play with respect to the axis ofthe median arm for adjustment of the median arm 5. This is illustratedin the figures, which show that the cavity 6 of the distal end has aconcave bottom surface of spherical shape with identical sphericity tothe ball joint 1 and has parallel lateral faces 7 and 8 which aremutually separated preferably by a distance greater than the width ofthe ball joint 1, in other words, greater than the distance between thefaces 2 and 3 of said ball joint. Said recess 6 also comprises, in itsinlet orifice 9, an aperture determined by the edges 10 and 11 which isnarrower than the diameter of the ball joint 1 in its spherical portionto allow fitting of the ball joint in the interior of the recessintended therefor by means of a specific pressure which will causesufficient deformation for the admission of the ball joint and whichwill not allow the free escape thereof.

The present improvements therefore simplify production of thedistalisation element by eliminating the arrangement of transverse axesand allowing easy fitting of the median segment and sufficient rotationthereof for the correct fitting thereof.

Although the invention has been described with reference to theillustrated example, it will be appreciated that it could similarlycomprise different variations included within the field of the followingclaims. Thus, for example, the caps of the ball joint might not beplanar, similarly to the lateral faces of the receiving cavity, and thesurface of the ball joint might have a non-spherical curved structure.Similarly, the angle α might have a value of zero.

1. Improvements to the subject of the main patent No. 200102210 for an“Auxiliary element for the segmental distalisation of thecanine-to-molar posterior maxillary area in orthodontic treatments”,characterised in that the ball joint of the median segment is sphericalwith two diametrically opposed planar faces in the position of polarsegments of the sphere.
 2. Improvements to the subject of the mainpatent No. 200102210 for an “Auxiliary element for the segmentaldistalisation of the canine-to-molar posterior maxillary area inorthodontic treatments”, according to claim 1, characterised in that thearm of the median segment is joined to the ball joint, forming a smallacute angle.
 3. Improvements to the subject of the main patent No.200102210 for an “Auxiliary element for the segmental distalisation ofthe canine-to-molar posterior maxillary area in orthodontic treatments”,according to claim 1, characterised in that the recess of the distalsegment intended to receive the ball joint has a form which partiallymates with that of the ball joint, with a width between faces which issomewhat greater than the width between the faces of the ball joint soas to allow the lateral play thereof and play on the axis of the medianarm and with a dimension of the inlet orifice of said recess smallerthan the diameter of the ball joint so as to allow the ball joint to bepressed in and to prevent the subsequent accidental egress thereof.